If you haven't seen it already, I would recommend "The Chosen"! The first episode of Season 2 can be viewed by clicking here!
The Nuttall Encyclopedia
See Aix-la-Chapelle .
Wood, James, ed. Entry for 'Aachen'. The Nuttall Encyclopedia. https://www.studylight.org/encyclopedias/eng/nut/a/aachen.html. Frederick Warne & Co Ltd. London. 1900.